is directly proportional to . When , . What is when ?
Answer and explanation
Correct answer: A. 21
- Step 1: Direct proportion means . From , .
- Step 2: When : .
Answer
21.
Why not the others: 15: This adds the increase in to , which is an additive rather than proportional method. 6.9: This treats it as inverse proportion by using . 84: This multiplies by the new value of without dividing by the old.
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